code: def test_labels(self):
      plt.close("all")
      g = Graph.Ring(5)
      fig, ax = plt.subplots(figsize=(3, 3))
      plot(
          g,
          target=ax,
          layout=self.layout_small_ring,
          vertex_label=["1", "2", "3", "4", "5"],
          vertex_label_color="white",
          vertex_label_size=16,
      )
  
imports: import os
  import unittest
  from igraph import Graph, plot, VertexClustering, Layout
  from ...utils import overridden_configuration
label_desc: Use image node_id 4 for calling the GraphTestRunner obj's underlying member method code with example usage: obj.test_labels() without return types